Table 2.3 Quantitative results of bronze BrA9Zh3L X-ray energy-dispersive analysis
Spectrum
Components quality, wt. %
Copper
Aluminum
Iron
Zinc
Spectrum 1
7.72
9.86
81.20
0.35
Spectrum 2
6.03
10.23
82.03
0.15
Spectrum 3
6.13
10.39
82.79
0.68
Spectrum 4
7.17
9.98
81.89
0.0
Spectrum 5
6.05
10.11
82.17
0.0
Source: completed by the authors
3. Phase composition and structure of industrial bronze BrA9Zh3L
additionally doped with Zn. Normative requirements of GOST 493 [4] (see Table
2.1) analysis indicate that bronze BrA9Zh3L contains impurities, besides the main
components Cu, Al and Fe. Among them the greatest amount is found on zinc (up to
1.0 wt. %) without change of industrial alloy grade. It is known [11, 23] that, in
accordance with foundry stable-established practice, modern technology uses bronzes
doping with zinc to enhance the bronze liquidity. At the same time, according to data
[11], with amount of zinc increasing in alloy not only liquidity of bronzes rises, but
also its structure and level of mechanical properties changes.
Investigated alloys microstructures are shown in Figure 3.1. Figure 3.1 analysis
demonstrates that the structure of bronze BrA9Zh3L with zinc content as per GOST
493 [4] (Figure 3.1, a, b, c) as well as industrial bronze BrA9Zh3L additionally doped
with zinc (Figure 3.1, d, e, f) consists of α-Cu solid solution and multiphase eutectoid
structural component. It is obvious, that with rising of zinc concentration in alloys
amount of eutectic component continuously increases (Figure 3.2).
a
b
c
d
e
f
a – 0%Zn, b – 0,4%Zn, c – 0,6%Zn, d – 1,4%Zn, e – 2,5%Zn, f – 4,0%Zn,
Figure 3.1. Microstructures (× 100) of bronze BrA9Zh3L with different zinc
content
(wt. %)
Source: investigated by the authors
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